Rotary slip



Feb. 18, 1941. Q KQEN 2,231,923

ROTARY SLIP Original Filed Dec. 2, 1935 4 Sheets-Sheet 1 Lee 0. Koeri Feb. 18, 1941.

L. 0. KOEN ROTARY SLIP Original Filed Dec. 2, 1955 4 Sheets-Sheet 2 Lee 0. Kan

Feb. 18, 1941. 1 Q KQEN 2,231,923

ROTARY SLIP Original Filed Dec. 2, 1955 4 Sheets-Sheet 5 Feb. 18, 1941. L. o. KOEN 2,231,923

ROTARY SLIP Original Filed Dec. 2, 1935 4 Sheets-Sheet 4 Lee 0. Koen Patented Feb. 18, 1941 UNITED- STATES PATENT OFFICE ROTARY SLIP Lee 0. Koen, Houston, Tex.

6 Claims.

This invention relates to new and useful improvements in rotary slips.

With the increasing depth to which oil wells are drilled with rotary rigs, it has become necessary to increase the strength and size of the a ;e;.drilling apparatus. The increased length of the "firm pipe, or stem has added excessive weight.

and, therefore, the slips which hold the pipe in the rotary table have necessarily been changed. In order to provide sufilcient gripping surface to carry the load imposed by the length of pipe,

the slips have been lengthened and manifestly,

proved means for hydraulically exerting an up-- ward force against pipe slips, either for dislodg- .ing them from their seat and elevating or assisting in elevating them and holding them in an elevated position.

Another object of the invention is to provide improved hydraulically-operated auxiliary lifting or counter-balancing means connected with the slips so as to aid in lifting said slips and particularly to support them and, to a desired extent, resist the lowering of said slips, whereby the load placed. upon the workmen is reduced and the operation accelerated.

An important object of the invention is to provide an improved slip structure provided with hydraulic actuating means for raising and lowering the slips, whereby a constant force may be exerted for lifting the slips and a steady and even cushioned lowering, is obtained.

A further object of the invention is to provide an improved slip assembly wherein either a liquid or a fluid may be used to actuate a reciprocating element for lifting and counter-balancing the slips, or wherein a liquid aided by mechanical means may be used to counter-balance the slips or aid in lifting the same. It is pointed out that the invention may be employed either to aid the workmen or to perform the raising and lowering of the slips and thus relieve the workmen entirely.

A construction designed to carry out the invention will be hereinafter described, together with other features of the invention.

The invention will be more readily understood from a reading of the following specification and by reference to the accompanying drawings, in which an'example of the invention is shown, and wherein:

Figure 1 is a plan view of a slip mechanism constructed in accordance withthe invention,

Figure 2 is a view of the same, partly in elevation and partly in section, showing the slips lowered in pipe gripping position,

Figure 3 is a transverse, vertical sectional view showing the slips in elevated position,

Figure 4 is a similar view taken on the line 4-4 of Figure 2,

Figure 5 is a horizontal, cross-sectional view taken on the line 5-5 of Figure 2,

Figure 6 is a similar view taken on the line 6-6 of Figure 2,

Figure '7 is a transverse, vertical sectional view, similar to Figure 2, showing a modified form of lifting means, and

Figure 8 is a partial, vertical sectional view of another form of lifting means.

This application is filed as a division of my co-pending application, Serial No, 52,546, filed December 2, 1935.

In the drawings, the numeral l designates an ordinary rotary table such as is commonly used with rotary well drilling rigs. Such tables have a central socket or opening H which is arranged to receive a flanged bushing l2. It is customary to construct the bushing in two sections so that the same may be removed when desired andreplaced when the usual drill pipe or stem i3 is employed. A bowl it, having an upwardly inclined or tapered bore I5, is mounted on top of the rotary table and has its reduced lower end l6 engaging within an enlarged annular recess I! which surrounds the upper end of the bore of the bushing ii. A plurality of arcuate slips or slip members it, having serrations or teeth l9 formed on their inner surfaces 20, are adapted to engage within the bore I of the bowl, whereby the teeth I9 are caused to grip the pipe [3 when said slip members are lowered into said bowl as shown in Figure 2. Altogether six slip members are shown, it is to be understood that any number suitable for this purpose may be used.

A dove-tailed groove 2| is disposed transversely within the outer surface 20 of each slip member so as to form an annular recess for receiving 'a pair of semi-circular or arcuate latch sectors or cylinder.

segments 22 which are hinged together by a pin 23. Each sector is provided with an outwardly extending handle which has a hand grip 24 formed on its outer end. One handle 25 is made integral with one of the sectors, while the other handle 28 is hinged at 26' to the other sectors. The handle 25 is provided with a latch keeper 21-, while the swinging handle 26 has a latch hook 28 arranged to engage the keeper when the bandles are swung together, whereby the sectors 22 are fastened together around the slips and form a ring therefor.

The parts are so proportioned that when the sectors are latched together, the slip members l8 will be secured to the pipe I! because of the "bite or grip of the teeth l8 brought about by the pressure exerted in latching the sectors together. As shown in Figure 3, the sectors have a very loose lit in the grooves 2|, whereby the slip members are free to undergo independent movement. Thus, the members are self-adjusting and may swing to a limited extent. In order to prevent creeping of the members on the sectors, a notch or recess 28 is provided in the upper edge of each member and are arranged to receive the heads of a plurality of machine screws 38 mounted in the sectors. These screws do not fit closely in the notches and, therefore, do not interfere with the swinging movement of the slip members.

A cylindrical housing or shell 8| surrounds the bowl i4 and is connected thereto by an annular top 32 and bottom 33, whereby an annular chamber or reservoir 34 is formed between said bowl and housing. A hydraulic cylinder 35, having an external radial shoulder 38 intermediate itsends, is suspended within the reservoir 34 so that its open lower end is spaced a slight distance above the bottom 83 of said reservoir. The shoulder 38 is provided with a reduced screw-threaded lower portion which is arranged to engage within a screw-threaded opening 31 formed in the top 32 of the reservoir, whereby the cylinder 35 is mounted therein and projects above the'surface of the said top.

An elongate, cylindrical detent or plunger 28, having rounded ends, is disposed axially within the cylinder and is supported therein by having its rounded lower end engaging within the axial socket or recess of a piston 38 which has a snug sliding fit within said cylinder. An upwardly extending, outwardly curved hanger 48 is made integral with one of the latch sectors 22 at a point adjacent the cylinder 35. A lateral head 4i, having a socket 42 formed in its underside is providedv on the outer end of the hanger 48, whereby the head overhangs the upper end of the The rounded upper end of the detent 88 projects through the upper end of the cylinder so as to engage within the socket 42 of the head 4i and may be secured to the latter by a suitable screw 43, whereby said detent is connected by the hanger 40 to one of the sectors 22. This arrangement provides a simple connection and permits a free rocking movement of the slip members.

The reservoir 34 is partially filled with a suitable fluid so as to provide a large air space or chamber thereabove. By introducing air under pressure .into the reservoir by means of a valve 32 provided in the top 82, the liquid within said reservoir is forced upwardly into the cylinder 35,

thereby elevating the piston 38 and rod 88 and in turn lifting the slips. It is noted that if the slips are latched on the drill stem or pipe IS, the same may be raised thereby and the hydraulic .age of the pipe.

lift used to sustain said slips in their elevated position. However, if the clips are not latched on said pipe, the same may be lifted by the hydraulic means. The air space in the reservoir is of such size that the upward and downward movement of the piston 28 within the cylinder 35 will cause only slight pressure changes as shown in Figure 3, the pressure actuated rod88 will support the ring formed by the sectors 22 at a suflicien't height to permit the slip members l8 to be swung outwardly over the bowl l4.

When the device is being used, the slips are swung together and latched as shown in Figure 1. The hand grips 24 may be grasped by a workman so as to swing the handles 25 and 28 together. When the hook 28 has engaged the keeper 21, the teeth l8 of the slip members will 8riD the surface of the pipe i8. This gripping action is accentuated by the sliding and wedging contact between the fiat adjacent faces of the hook and keeper. Since the slip members are latched on the pipe, it is obvious that the same will be carried downwardly with said pipe when the latter is lowered, whereby the inclined outer surfaces 28 of said members will engage within the bore i5 of the bowl l4. This forcing of the slips into the bowl assures a proper and safe anchor- When the slip members are moved downwardly the valve 82 is opened so as to exhaust the compressed air, whereby the rod 38 and piston will slide downwardly within the cylinder 35.

When it is desired to release the slips, the pipe is raised in the usual manner to lift the slip members from the position shown in Figure 2 to the position shown in Figure 3. In this manner, the slips will be forcibly pulled out of the bore II of the bowl l4. However, the liquid within the reservoir 34 may be compressed, as hereinbefore set forth, to force the piston 38 and rod 88 upwardly, whereby the compressed liquid assists in lifting the slips to their upper position. It is pointed out that the principal function of the compressed liquid is to support the rod and piston in an elevated position, whereby the slips will be supported. When the slips have been moved to their upper position, the handle 28 may be swung manually to disengage the latch and then both handles may be swung'so as to swing the slip members away from the pipe.

It is noted that the pressure actuated rod and piston may be utilized to assist in elevating the slips. If the teeth IQ of the slip members retain their rip on the p p the slips will be elevated when said pipe is raised. However, if the slips should lose. their grip on the pipe and start to slide downward thereon when the latter is raised, the pressure-actuated rod and piston will raise or assist in the manual raising of the slips.

In Figure 7, a modified form of the invention is shown and includes the usual rotary table l8 and flanged bushing i2'.- An elongate, vertical well or chamber 43 is provided in the rotary table and extends upwardly through the flange of the bushing and a cylindrical boss 44 which projects above the top of the bushing. The well or chamber provides a smooth cylindrical bore to receiving an elongate piston or plunger 45, hich has a sliding fit therein. A flexible pac cup 46 is secured to the lower end of the plunger, while a cap 41 is mounted upon the upper end of said plunger.

A yoke 48, having a hollow block 49 pivoted therein, is carried by the cap 41. A cylindrical trunnion 50 engages within the block 48 andhas provided on its inner end with a reduced eye 54 which engages between the ears'x53 and is securedthereto by a pin 55, whereby the ring is hinged to the trunnion. The lifting ring has a loose fit in the slip =mem'bers so as not to interfere with their swinging-movement. It will be observed that the pin 23- of the latch ring overlies the hinge pin- 55 of the lifting ring, whereby the slip sections which "are; defined .by the sectors may be freely swung open when the device is unlatcheda a A vertical duct- 56, extending down through the rotary table is provided with a lateral extension 51 which communicates with the bottom of the well '43. A hydraulic cylinder 58 is mounted on the table and has a piston 59 slidably disposed therein. A short pipe 50 connects the forward portion of the cylinder to the upper end of the duct 56. A suitable liquid such as oil, is placed in the cylinder and fills the ducts 56 and 51 and the well 43 below the plunger 45. The piston 59 is provided with a piston rod 6| which extends through an adjustable head 62 screw-threaded into the rear end of the cylinder. A coiled spring 63 surrounds the rod 61 and is confined between the head 62 and the piston 59.

With the slips lowered into the bushing i2 and the plunger in its lower position as shown,

the liquid within the well 43 is forced into the cylinder 58 and the piston 59 displaced, whereby the spring! is compressed. By adjusting the head 52, the degree to which the spring is compressed may be varied so as to obtain the desired slip balance. When the slip members l8 are lifted to their upper position, the compressed spring force; the liquid from the cylinder through the ducts in the well 43, thereby tending to lift the plunger 45 in much the same manner as the compressed liquid in the hereinbefore described form.

In Figure 8, another hydraulic form is shown wherein the slips 64 are formed of two semicircular sectors or sections, hinged together in the usual way. The bushing 65 has a reservoir or chamber 65 and an inclined bowl 61 conforming to the slips. Each slip sector has a handle 58 loosely connected thereto and provided with a rigid depending piston 69, slidably confined within a cylinder 10 which extends down into the reservoir 86. The cylinders and pistons have the same inclination as the bowl 6! and when said pistons are actuated, similarly to the piston 39 of the first form, they will raise and lower the slip sectors.

In this form, the slips will become disengaged from or release the pipe after the initial upward movement of the same. The handles 58 may be detachably connected to the pistons 59 so as to permit removal of the slips without removin the pistons. It is pointed out that this device will serve mainly as a coimter-balancing means to decrease the amount of manual labor. when no latching means is employed, it is obvious that the pipe will not move the slips, except perhaps .during its --initial'-;upward movement unless the handles B8-are-. manlpulated so as to grip said slips on; said pipe..- If this is not done, the slips will .be raised and lowered only by the hydraulic means and will be, of course, counter-balanced, in any position, by-controlling said hydraulic means.

While the slips have been shown with teeth i9 forgripping the pipe, it is to be understood that said slips may be provided with any suitable means for gripping. the pipe,- so long as they retain their hold on. said pipe and are moved therebywhen brought :into gripping position on the same. It is manifest .-that the latching means may be entirely. eliminated or used in any suitable form. It has been found expedient to illustrate means for' manually opening and closing-theslips, but any suitable means may be employed for this purpose.

Various changes, alterations and modifications may be made in the size, shape and arrangement of the herein described elements, within the scope of the appended claims.

What I claim and desire to secure by Letters Patent is:

1. A pipe slip, including a slip bowl, a hydraulic plunger mounted uprightly on the bowl, a plurality of pipe slips, a hinged supporting member engaging around the slips and provided with a releasable latching means, said supporting means being connected to said plunger.

2. A pipe slip includin a slip bowl, a hydraulic plunger mounted upright on the bowl, a plurality of pipe slips, a pair of .hinged' supporting members carrying said slips and provided with a releasable latching means, said member being supported by said plunger, and said plunger being of sufilcient length to raise the bottom of said slips above said bowl.

3. A pipe slip including, a slip bowl, a hydraulic plunger mounted uprightly on the bowl, a plurality of pipe slips, a pair of hinged supporting members carrying said slips and provided with a releasable latching means, said member being supported by said plunger, and said plunger being of suflicient length to raise the bottom of said slips above said bowl so that I a plurality of slips, a slip supporting member engaging around the slips, said member being supported by said plunger, and said plunger being of sufllcient length to raise the bottom of said slips above said bowl so that said slips when raised above said bowl may be manually swung laterally.

6. A pipe slip device including, a slip bowl, a hydraulic plungerdisposed .uprightly on the bowl, and pipe supporting elements carried by and movable with the plunger, said plunger be ing oi such length as to move the slips entirely out of the bowl.

- LEE 0. KOEN. 

